Radio receiving apparatus, and method for detecting a delay differential between branches in the apparatus

ABSTRACT

Delay profiles of respective branch received signals received through a plurality of antennas are formed; peaks on each of formed delay profile signals are detected; the maximum peaks are obtained among detected peaks on the respective delay profile signals; and average delay differentials between the delay profiles are obtained by averaging a desired number of delay differentials among the maximum peaks.

This application is a 371 of PCT/JP01/08501 filed on Sep. 28, 2001.

TECHNICAL FIELD

The present invention relates to a radio receiving apparatus fordemodulating by using a plurality of received signals obtained with aplurality of antennas, and a method for detecting a delay differentialbetween branches in the apparatus.

BACKGROUND ART

A method, in which delay profiles are formed for respective receivedsignals obtained through each antenna in a radio receiving apparatususing a plurality of antennas and are combined is known to be effectivefor searching paths (see Radio Communication Systems (RCS), theInstitute of Electronics, Information, and Communication Engineers(IEICE), Report 99-67, July, 1999).

However, there are cases where delay periods from antennas to receivingbaseband processing means vary depending on received signals of eachantenna (hereinafter called branch received signals). One of the mainreasons for this is the variety in the delay characteristics ofreceiving filters. Cases like above might render the delay profilecombination less effective and might even lead to deterioration.Similarly, in a radio receiving apparatus comprising an array antenna,an apparatus for forming delay profiles using signals combining eachbranch received signal has a similar problem.

Conventionally, one method for detecting delay differentials betweenindividual branch received signals is to measure on a per path basis theprocessing times of the filters arranged directly behind antennas anddelay periods caused by the resistance on the signal lines betweenantennas and the baseband processing means and thus obtain the delaydifferentials.

A second method is to measure on a per path basis the delay period fromthe point a reference signal is input from an antenna to a radioreceiving apparatus to the point this signal reaches a basebandprocessing means, input a reference signal from the antenna to the radioreceiving apparatus, and thus obtain differential delays.

However, in a conventional apparatus, a problem with the first method isthat the method requires a number of steps to measure and adjust theprocessing times of the filters and delay periods on signal lines oneach path between an antenna and baseband processing means.

With respect to the second method, there is a possibility that areference signal becomes an interference source, as the referencesignal, which is not required for ordinary transmission and receiving,is input, and it is required that delay periods on respective pathsbetween the antenna and baseband processing means are measured, andadjusted. Another problem is that an ordinary received signal may not bereceived there between.

DISCLOSURE OF INVENTION

The object of the present invention is to detect delay differentials ofrespective branch received signals between a plurality of antennas andbaseband processing means in an easy and accurate manner.

The object is achieved as follows: delay profiles of respective branchreceived signals received through a plurality of antennas are formed;peaks in each of formed delay profile signals are detected; the maximumpeaks are obtained from among the detected peaks in the respective delayprofile signals; and average delay differentials between the delayprofiles are obtained by averaging out a desired number of delaydifferentials among the maximum peaks.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing a configuration of a radio receivingapparatus according to an embodiment 1 of the present invention;

FIG. 2 shows waveforms of delay profile signals, formed in a delayprofile forming section of the radio receiving apparatus according toembodiment 1, for the first and second branches;

FIG. 3 is a block diagram showing a configuration of a delaydifferential detection profile combination section in the radioreceiving apparatus according to embodiment 1;

FIG. 4 is a block diagram showing a configuration of a radio receivingapparatus according to embodiment 2 of the present invention;

FIG. 5 is a block diagram showing a configuration of a radio receivingapparatus according to embodiment 3 of the present invention;

FIG. 6 shows other waveforms of delay profile signals formed in thedelay profile forming section of the radio receiving apparatus accordingto any one of embodiments 1-3, for the first and second branches;

FIG. 7 is a block diagram showing characteristics of anotherconfiguration of the radio receiving apparatus according to any one ofembodiments 1-3;

FIG. 8A shows a waveform that describes one of the effects ofapplication examples according to embodiments 1-3;

FIG. 8B shows a waveform that describes another effect of applicationexamples according to embodiments 1-3; and

FIG. 8C shows a waveform that describes a still another effect ofapplication examples according to embodiments 1-3.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described indetail, referring to attached drawings.

(Embodiment 1)

FIG. 1 is a block diagram showing a configuration of a radio receivingapparatus according to embodiment 1 of the present invention.

A radio receiving apparatus 100, shown in FIG. 1, which is configured asa diversity antenna or an array antenna, and in which delaydifferentials on a plurality of paths between each antenna and basebandprocessing means are detected and corrected, comprising: a delay profileforming section 101; a delay differential detection profile combinationsection 102; a path search section 103; a finger assign section 104; adespreading section 105; a demodulation section 106; and a decodingsection 107.

The components 101-107 are arranged at the input side in the basebandprocessing means, and the delay profile forming section 101 is connectedto the back of an analog-digital converter in which analog receivedsignals, which arrive through filters after they are received throughtwo not-shown antennas, of a first and a second branches are convertedinto digital signals.

The delay profile forming section 101 forms delay profiles shown in FIG.2 by correlating the first and second branch received signals with knownsignals. FIG. 2 shows signal waveforms of the delay profiles for thefirst and second branches.

In FIG. 2, 201 is a first branch delay profile signal (hereinafter,called a first delay profile signal), and 202 is a second branch delayprofile signal (hereinafter, called a second delay profile signal).

The delay differential detection profile combination section 102 detectsa delay differential between the first and the second delay profilesignals formed in the delay profile forming section 101; at the sametime, forms a combination delay profile signal combining the first andthe second delay profile signals; and has a configuration shown in FIG.3.

That is, the delay differential detection profile combination section102 comprises, as shown in FIG. 3: a peak detection section 301; a delaydifferential averaging processing section 302; a delay section 303; anda profile combination section 304.

The peak detection section 301 detects peaks on the first and the seconddelay profile signals 201, 202, which are shown in FIG. 2, and outputsthe detected peaks to the delay differential averaging processingsection 302.

The delay differential averaging processing section 302 obtains everymeasurement period a desired number of delay differentials. between themaximum peaks on the first and the second delay profile signals 201, 202which are shown in FIG. 2, and the delay differentials are obtained byaveraging the obtained delay differentials. The delay differentials areoutput to the delay section 303 and the finger assign section 104.

The delay section 303 delays the first delay profile signal according tothe delay differential obtained in the delay differential averagingprocessing section 302 so that the first delay profile signal has thesame phase as that of the second delay profile signal, and outputs thedelayed signal to the profile combination section 304.

The profile combination section 304 combines the first and the seconddelay profile signals which have the same phase, and outputs theobtained combination delay profile signal obtained above to the pathsearch section 103.

The path search section 103 detects the phase of a peak from thecombination delay profile signal, and outputs it to the finger assignsection 104.

The finger assign section 104 recognizes the delay differential betweenthe first and the second branch received signals input to thedespreading section 105, using the delay differential input from thedelay differential detection profile combination section 102, andindicates timing, by which the peak phase from the path search section103 is shifted by the delay differential, to the despreading section 105as despreading timing of the first and the second branch receivedsignals.

The despreading section 105 despreads the first and second branchreceived signals at the indicated despreading timing. The despreadingsignal obtained above is demodulated in the demodulation section 106,and, subsequently, is decoded in the decoding section 107 together withthe rake combination.

As described above, the radio receiving apparatus 100 of embodiment 1has been configured that delay profiles of the first and the secondbranch received signals received through each antenna are formed in thedelay profile forming section 101, peaks in the first and second delayprofile signals are detected in the peak detection section 301, themaximum peaks are obtained among the peaks in the first and the seconddelay profile signals in the delay differential averaging processingsection 302, respectively, and the delay differentials are obtained byaveraging a desired number of delay differentials with regard to theobtained maximum peaks.

Thereby, the delay differentials between each branches received signalfrom a plurality of antennas to the baseband processing means may beeasily and accurately detected.

Moreover, it is configured such that each delay profile signal has thesame phase in the delay section 303 by delaying according to the delaydifferential a delay profile signal with a phase lead of the first orthe second delay profile signal, and the delay profile signals whichhave the same phase are combined in the profile combination section 304.

Thereby, combination delay profiles on which actual paths are favorablyreflected may be obtained, as the combination delay profiles may beformed, using the delay profiles without the delay differential betweenthe branches.

It has been also configured that the peak phase is detected from thecombination delay profile signal in the path search section 103, andtiming by which the peak phase is shifted by the above-described delaydifferential in the finger assign section 104 is set for the despreadingtiming of the first and the second branch received signals.

Thereby, the size of a circuit for correcting the delay differential isnot required to be increased, as the delay differential between thebranches is corrected by the timing of the despreading.

(Embodiment 2)

FIG. 4 is a block diagram showing a configuration of a radio receivingapparatus according to embodiment 2 of the present invention. Here, inembodiment 2 shown in FIG. 4, parts corresponding to those of anembodiment 1 in FIG. 1 are denoted by the same reference numbers asthose in FIG. 1, and the description will be eliminated.

A radio receiving apparatus 400 shown in FIG. 4 comprises: a fingerassign section 401; and a delay section 402; as well as a delay profileforming section 101; a delay differential detection profile combinationsection 102; a path search section 103; a despreading section 105; ademodulation section 106; and a decoding section 107, which arecomponents in embodiment 1.

In the above configuration, the delay section 402 delays a first branchreceived signal according to a delay differential output from the delaydifferential detection profile combination section 102 so that the firstbranch received signal has the same phase as that of the second branchreceived signal, and outputs the delayed signal to the despreadingsection 105.

The finger assign section 401 indicates a peak phase from the pathsearch section 103 to the despreading section 105 as despreading timingof the first and the second branch received signals.

Thus, it is configured in the radio receiving apparatus 400 according toembodiment 2 that the first and the second branch received signals havethe same phase by delaying according to the delay differential a branchreceived signal with a phase lead of the first or the second branchreceived signal in the delay section 402.

Thereby, the delay differentials of respective branch received signalsreceived through the first and the second antennas and input to thedespreading section 105 may be easily corrected.

(Embodiment 3)

FIG. 5 is a block diagram showing a configuration of a radio receivingapparatus according to embodiment 3 of the present invention. Here, inembodiment 3 shown in FIG. 5, parts corresponding to those of anembodiment 1 in FIG. 1 are denoted by the same reference numbers asthose in FIG. 1, and the description will be eliminated.

A radio receiving apparatus 500 shown in FIG. 5 comprises: a fingerassign section 501; and a delay section 502; as well as a delay profileforming section 101; a delay differential detection profile combinationsection 102; a path search section 103; a despreading section 105; ademodulation section 106; and a decoding section 107, which arecomponents in embodiment 1. However, the delay differential detectionprofile combination section 102 in embodiment 3 has a configurationwithout a delay section 303.

In the above configuration, the delay section 502 delays a first branchreceived signal, which is input to the delay profile forming section101, and the despreading section 105, according to a delay differentialoutput from the delay differential detection profile combination section102 so that the first branch received signal has the same phase as thatof the second branch received signal.

The finger assign section 501 indicates a peak phase from the pathsearch section 103 to the despreading section 105 as despreading timingof the first and the second branch received signals.

Thus, it is configured in the radio receiving apparatus 500 according toembodiment 3 that the first and the second branch received signals havethe same phase in the delay section 502 by delaying, according to thedelay differential from the delay differential detection profilecombination section 102, a branch received signal, which has a phaselead, of the first or the second branch received signal input to thedelay profile forming section 101.

Thereby, combination delay profiles on which actual paths are favorablyreflected by correcting the delay differentials of respective branchreceived signals may be obtained, as feed back control of amounts ofdelay for the first and the second branch received signals by the delaysection 502 is performed based on an average delay differential, whichis obtained in the delay profile combination section 102, between thedelay profiles.

Besides, it may be configured in the delay differential detectionprofile combination section 102 which is a component in theabove-described embodiments 1-3 that there is set a window defining arange by which paths are identified as the same when a peak is detectedon the first and the second delay profile signals in a peak detectionsection 301, and peaks of the first and the second delay profile signalswhich pass through the window are output to a delay differentialaveraging processing section 302.

In this case, the following advantages may be obtained. It is assumedthat the first branch delay profile signal 601 and the second branchdelay profile signal 602, waveforms of which are shown in FIG. 6, areformed in the delay profile forming section 101, and are output to thepeak detection section 301.

In this case, it is assumed that a peak of the second delay profilesignal 602 is 602-P1, corresponding to a peak 601-P1 of the first delayprofile signal 601. However, there is a possibility that a peak 602-P2is judged as the peak corresponding to the peak 601-P1 by mistake in thedelay differential averaging processing section 302, as the peak 602-P2away from the peak 602-P1 is larger in amplitude.

Then, erroneous averaging processing in which a not-target peak is usedmay be eliminated by detecting peaks after setting in the peak detectionsection 301 a window with a range by which only 602-P1 corresponding to601-P1 passes through it, when the amplitude of the not-target peak awayfrom a target peak is larger in the other delay profile signal.Therefore, the total time for obtaining the delay differentials by theaveraging processing may be shortened.

Moreover, it may be configured that, in the delay differential averagingprocessing section 302, the delay differential may be obtained not byaveraging processing in which only the maximum peaks are used asdescribed above, but by averaging processing using Nth peaks such as thesecond peaks, and the third peaks. In this case, the total time forobtaining the delay differentials may be also shortened.

In addition, it may be configured that cross correlation of delayprofiles between branches is calculated, using the delay profiles in asection where there are the upper N number of peaks, and the amount ofshift (time) of the delay profile by which the maximum peak appear maybe the delay differential between both branches. In this case, the totaltime for obtaining the delay differentials may be shortened, too.

Furthermore, a delay section 701 and a changeover switch 702 areprovided, as shown in FIG. 7, on either of branches (here, the secondbranch) which are connected to the input side of the delay profileforming section 101. Here, the amount of delay in the delay section 701is configured to be smaller than a sampling interval of the delayprofile.

The changeover switch 702 is switched to the side of the delay section701 and the other non-delay side. At this time, the following processingis performed in the delay differential averaging processing section 302:A peak of the second delay profile signal formed by the side of thedelay section 701, a difference between the above peak and a peak of thefirst delay profile signal corresponding to the above peak, andinformation on the amplitude of the peak of the second delay profilesignal at this time are stored.

Similarly, a peak of the second delay profile signal formed by thenon-delay side, a difference between the above peak and a peak of thefirst delay profile signal corresponding to the above peak, andinformation on the amplitude of the peak of the second delay profilesignal at this time are stored.

Then, averaging processing adopting a difference corresponding to theinformation on the larger amplitude is performed, and the delaydifferential is obtained.

Thereby, the delay differential can be obtained at shorter intervalsthan the sampling intervals of the delay profile, when the amount ofdelay at delay is set as shorter intervals than the sampling intervalsof the delay profile. For example, a waveform with shorter intervals, asshown in FIG. 8C, in which waveforms in FIG. 8A, and FIG. 8B arecombined can be obtained as shown in FIG. 8A-FIG. 8C.

Though, cases where timing, by which peak phases are shifted by theamount of the average delay differential corresponding to each branch,is set for despreading timing of respective branch received signals havebeen described in the above-described embodiments, the present inventionis not limited to the above-described embodiments, and the above timingmay be used as demodulating timing of the demodulation section.

In addition, the present invention is not limited to the above-describedembodiments, and various variations and modifications may be possible.

The radio receiving apparatus according to the present invention employsa configuration that comprises, delay profile forming means that forms adelay profile for each of individual branch received signals received bya plurality of antennas, peak detection means that detects a peak ineach delay profile signal formed by said delay profile forming means,and delay differential averaging processing means that obtains a maximumpeak in each delay profile signal from among the peaks detected by saidpeak detection means and that obtains an average delay differentialamong individual delay profiles by averaging out a desired number ofdelay differentials between the maximum peaks.

With this configuration it is made possible to detect with simplicityand accuracy a delay differential that develops between received signalsunder individual branches in the course between a plurality of antennasand baseband processing means.

The radio receiving apparatus according to the present invention employsa configuration that further comprises, delay means that delays a delayprofile signal with a leading phase from among individual delay profilesby an average delay differential among the individual delay profiles,and adjusts the phases of individual profile signals the same, andprofile combining means that combines the delay profile signals of thesame phase.

With this configuration it is made possible to correct an inter-branchdelay differential with simplicity. It is also possible, since correcteddelay profiles are combined, to obtain a combined delay profile thatfavorably reflects an actual path.

The radio receiving apparatus according to the present invention employsa configuration that further comprises, path search means that detects apeak phase from a combined delay profile obtained by the combination bysaid profile combining means, and reception timing determining meansthat sets a timing obtained by shifting a peak phase by an average delaydifferential under a corresponding branch for a decoding timing for abranch received signal.

With this configuration, the paths on which actual paths are favorablyreflected may be accurately detected in the path search means, as thepeak phases are detected based on the combination delay profiles onwhich actual paths are favorably reflected. And demodulation operationmay be realized in a state in which the paths are under accuratesynchronization with incoming timing, as the peak phases which have beenaccurately detected are shifted by the corresponding average delaydifferential, and are set for the receiving timing in the receivingtiming decision means.

The radio receiving apparatus according to the present invention employsa configuration, wherein, when a branch received signal is a spreadsignal, said reception timing determining means sets a timing obtainedby shifting a peak phase by an average delay differential under acorresponding branch for a dispreading timing for a branch receivedsignal.

With this configuration it is made possible to correct with simplicity adifferential delay between branches at the timing of dispreading.

The radio receiving apparatus according to the present invention employsa configuration that comprises, delay profile forming means that forms adelay profile for each of individual branch received signals received bya plurality of antennas, delay differential detecting profile combiningmeans that obtains a maximum peak in each delay profile signal fromamong the peaks in a delay profile signal formed by said delay profileforming means, that obtains an average delay differential amongindividual delay profiles by averaging out a desired number of delaydifferentials between the maximum peaks, and that delays a leading delayprofile signal with a leading phase from among individual delay profilesignals by an average delay differential among individual delay profilesand combines the phases of individual profile signals the same, pathsearch means that detects a peak phase from a combined delay profilesignal obtained by the combination in said delay differential detectingprofile combining means, finger assign means that sets the peak phase adecoding timing for a branch received signal, and delay means thatdelays a leading delay profile signal from among individual branchreceived signals decoded by the decoding timing by an delaydifferential, and adjusts the phases of individual delay profile signalsthe same.

With this configuration it is made possible to correct with simplicityand accuracy a delay differential between branch received signalsreceived by a plurality of antennas.

The radio receiving apparatus according to the present invention employsa configuration that comprises, delay means that delays each of branchreceived signals received by a plurality of antennas by a phasecorresponding to each branch and adjusts individual branch receivedsignals to the same phase, delay profile forming means that forms adelay profile for each of individual branch received signals output fromsaid delay means, and delay differential detecting profile combiningmeans that obtains a maximum peak for each delay profile signal fromamong the peaks in a delay profile signal formed by said delay profileforming means, and that obtains an average delay differential amongindividual delay profiles by averaging out a desired number of delaydifferentials between the maximum peaks and combines individual delayprofile signals, said delay means, in accordance with delaydifferentials between delay profiles, delaying a branch received signalwith a leading phase by an average delay differential and adjusting thephases of individual branch received signals the same.

With this configuration it is made possible to form a combined delayprofile that favorably reflects an actual path by correcting a delaydifferential for each branch received signal, since the delay volume bydelay means for each branch received signal is controlled byfeedback-control based on the average delay differentials between thedelay profiles obtained by delay profile combining means.

The radio receiving signal according to the present invention employs aconfiguration that comprises, path search means that detects a peakphase from a combined delay profile obtained by the combination by saidprofile combining means, and finger assign means that sets the peakphase a decoding timing for an branch received signal.

With this configuration it is made possible to obtain with accuracy adecoding timing for each of individual branch received signals receivedby a plurality of antennas.

The radio receiving apparatus according to the present invention employsa configuration, wherein a range judged to be of the same path isdefined at the time of a peak detection of a delay profile signal andthe peak detection is performed within this range.

With this configuration and by thus defining a range where only thepeaks of other profile signals corresponding to the peaks of a certainprofile signal enter, and performing peak detection therein, it is madepossible to reduce the likelihood to erroneously perform averagingprocessing on these other delay profile signals with differing peaks,when a peak with a phase more distant than the a targeted peak is largerin amplitude. By this means, the total time to obtain a delaydifferential through averaging processing may be shortened.

The radio receiving apparatus according to the present invention employsa configuration, wherein a delay differential is obtained throughaveraging processing using the upper peaks to Nth.

With this configuration it is made possible to increase the number ofsamples of average delay periods and to thus shorten the total time forobtaining a delay differential.

The radio receiving apparatus according to the present invention employsa configuration that comprises, delay means that delays a branchreceived signal and switching means that switches delay and non-delayand outputs the switching to delay profile forming means, and wherein,when averaging processing of delay differentials is performed, a peak ina delay profile signal formed during a delay period, a phasedifferential with a corresponding peak in a delay profile signal under adifferent branch, and amplitude data of a peak in a delay profile signalformed during this delay period, and also a peak in a delay profilesignal formed during a non-delay period, a phase differential with acorresponding peak in a delay profile signal under a different branch,and amplitude data of a peak in a delay profile signal formed duringthis non-delay period, are memorized, and a delay differential isobtained by employing a phase differential corresponding to one of theabove two sets with larger amplitude data and performing averagingprocessing therewith.

With this configuration it is made possible to obtain a delaydifferential at intervals shorter than the sampling intervals of a delayprofile by setting the delay volume by the delay means with intervalsshorter than the sampling intervals of a delay profile.

The present invention is a mobile station apparatus that has a radioreceiving apparatus, and the radio receiving apparatus comprises, delayprofile forming means that forms a delay profile for each of individualbranch received signals received by a plurality of antennas, peakdetection means that detects a peak in each delay profile signal formedby said delay profile forming means, and delay differential averagingprocessing means that obtains a maximum peak for each delay profilesignal from among the peaks detected by said peak detection means andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks.

With this configuration, using a mobile station apparatus, it is madepossible to detect with simplicity and accuracy a delay differential ineach of individual branch received signals received by a plurality ofantennas.

The present invention is a base station apparatus that has a radioreceiving apparatus, and the radio receiving apparatus comprises, delayprofile forming means that forms a delay profile for each of individualbranch received signals received by a plurality of antennas, peakdetection means that detects a peak in each delay profile signal formedby said delay profile forming means, and delay differential averagingprocessing means that obtains a maximum peak for each delay profilesignal from among the peaks detected by said peak detection means andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks.

With this configuration it is made possible to correct with simplicityand accuracy a delay differential between individual branch receivedsignals received by a plurality of antennas.

The inter-branch delay differential detecting method according to thepresent invention is arranged such that, a delay profile is formed foreach of individual branch received signals received by a plurality ofantennas, a peak is detected in each of the formed delay profilesignals, and a maximum peak in each delay profile signal is obtainedfrom among the detected peaks, and an average delay differential betweenindividual delay profiles is obtained by averaging out a desired numberof delay differentials between the maximum peaks.

By this method it is made possible to detect with simplicity andaccuracy a delay differential between individual signals between aplurality of antennas and baseband processing means.

The inter-branch delay differential detecting means according to thepresent invention is arranged such that, a delay profile signal with aleading phase from among individual delay profiles is delayed by anaverage delay differential among individual delay profiles, and thephases of individual profile signals are adjusted the same, and thedelay profile signals of the same phase are combined.

Using this method it is made possible to correct an inter-branch delaydifferential with simplicity. It is also possible, since corrected delayprofiles are combined, to obtain a combined delay profile that favorablyreflects an actual path.

The inter-branch delay differential detecting means according to thepresent invention is arranged such that, a peak phase is detected from acombined delay profile signal obtained by combination processing, and atiming obtained by shifting a peak phase by an average delaydifferential under a corresponding branch is set a decoding timing for abranch received signal.

Using this method it is made possible to detect an adequate path thatfavorably reflects an actual path, since a peak phase is detected on thebasis of a combined delay profile that favorably reflects an actualpath. Moreover, since an adequately detected peak phase is shifted by anaverage delay differential and is set for a demodulating timing, it ismade possible to operate demodulation function with accuratesynchronization at the timing a path arrives.

The inter-branch delay differential detecting method according to thepresent invention is arranged such that, a branch received signal with aleading phase from among individual branch received signals is delayedby an average delay differential among individual delay profiles, andthe phases of the individual branch received signals are adjusted thesame.

Using this method it is made possible to correct with simplicity a delaydifferential in individual branch received signals received by aplurality of antennas.

As described above, using the radio receiving apparatus and inter-branchdelay differential detecting method in the radio receiving apparatus, itis made possible to detect with simplicity and accuracy delaydifferentials that develop between received signals under individualbranches in the course between a plurality of antennas and basebandprocessing means and to correct these delay differentials.

This application is based on the Japanese Patent Application NO.2000-300916, filed on Sep. 29, 2000, entire contents of which areexpressly incorporated by reference herein.

Industrial Applicability

The present invention is applicable to a radio receiving apparatus witha configuration in which received signals are demodulated, using thereceived signals obtained through a plurality of antennas, and a methodfor detecting a delay differential between branches in the apparatus.

What is claimed is:
 1. A radio receiving apparatus comprising: delayprofile forming means that forms a delay profile for each of individualbranch received signals received by a plurality of antennas, peakdetection means that detects a peak in each delay profile signal formedby said delay profile forming means, and delay differential averagingprocessing means that obtains a maximum peak in each delay profilesignal from among the peaks detected by said peak detection means andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks.
 2. The radio receiving apparatus according toclaim 1, further comprising: delay means that delays a delay profilesignal with a leading phase from among individual delay profiles by anaverage delay differential among the individual delay profiles, andadjusts the phases of individual profile signals the same, and profilecombining means that combines the delay profile signals of the samephase.
 3. The radio receiving apparatus according to claim 2, furthercomprising, path search means that detects a peak phase from a combineddelay profile obtained by the combination by said profile combiningmeans, and reception timing determining means that sets a timingobtained by shifting a peak phase by an average delay differential undera corresponding branch for a decoding timing for a branch receivedsignal.
 4. The radio receiving apparatus according to claim 3, wherein,when a branch received signal is a spread signal, said reception timingdetermining means sets a timing obtained by shifting a peak phase by anaverage delay differential under a corresponding branch for adispreading timing for a branch received signal.
 5. The radio receivingapparatus according to claim 1, wherein a range judged to be of the samepath is defined at the time of a peak detection of a delay profilesignal and the peak detection is performed within this range.
 6. Theradio receiving apparatus according to claim 1, wherein a delaydifferential is obtained through averaging processing using the upperpeaks to Nth.
 7. The radio receiving apparatus according to claim 1,further comprising: delay means that delays a branch received signal andswitching means that switches delay and non-delay and outputs theswitching to delay profile forming means, and wherein, when averagingprocessing of delay differentials is performed, a peak in a delayprofile signal formed during a delay period, a phase differential with acorresponding peak in a delay profile signal under a different branch,and amplitude data of a peak in a delay profile signal formed duringthis delay period, and also a peak in a delay profile signal formedduring a non-delay period, a phase differential with a correspondingpeak in a delay profile signal under a different branch, and amplitudedata of a peak in a delay profile signal formed during this non-delayperiod, are memorized, and a delay differential is obtained by employinga phase differential corresponding to one of the above two sets withlarger amplitude data and performing averaging processing therewith. 8.A radio receiving apparatus comprising: delay profile forming means thatforms a delay profile for each of individual branch received signalsreceived by a plurality of antennas, delay differential detectingprofile combining means that obtains a maximum peak in each delayprofile signal from among the peaks in a delay profile signal formed bysaid delay profile forming means, that obtains an average delaydifferential among individual delay profiles by averaging out a desirednumber of delay differentials between the maximum peaks, and that delaysa leading delay profile signal with a leading phase from amongindividual delay profile signals by an average delay differential amongindividual delay profiles and combines the phases of individual profilesignals the same, path search means that detects a peak phase from acombined delay profile signal obtained by the combination in said delaydifferential detecting profile combining means, finger assign means thatsets the peak phase a decoding timing for a branch received signal, anddelay means that delays a leading delay profile signal from amongindividual branch received signals decoded by the decoding timing by andelay differential, and adjusts the phases of individual delay profilesignals the same.
 9. The radio receiving apparatus according to claim 8,further comprising: path search means that detects a peak phase from acombined delay profile obtained by the combination by said profilecombining means, and finger assign means that sets the peak phase adecoding timing for an branch received signal.
 10. A radio receivingapparatus comprising: delay means that delays each of branch receivedsignals received by a plurality of antennas by a phase corresponding toeach branch and adjusts individual branch received signals to the samephase, delay profile forming means that forms a delay profile for eachof individual branch received signals output from said delay means, anddelay differential detecting profile combining means that obtains amaximum peak for each delay profile signal from among the peaks in adelay profile signal formed by said delay profile forming means, andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks and combines individual delay profile signals,said delay means, in accordance with delay differentials between delayprofiles, delaying a branch received signal with a leading phase by anaverage delay differential and adjusting the phases of individual branchreceived signals the same.
 11. A mobile station apparatus having a radioreceiving apparatus, said radio receiving apparatus comprising: delayprofile forming means that forms a delay profile for each of individualbranch received signals received by a plurality of antennas, peakdetection means that detects a peak in each delay profile signal formedby said delay profile forming means, and delay differential averagingprocessing means that obtains a maximum peak for each delay profilesignal from among the peaks detected by said peak detection means andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks.
 12. A base station apparatus having a radioreceiving apparatus, said radio receiving apparatus comprising: delayprofile forming means that forms a delay profile for each of individualbranch received signals received by a plurality of antennas, peakdetection means that detects a peak in each delay profile signal formedby said delay profile forming means, and delay differential averagingprocessing means that obtains a maximum peak for each delay profilesignal from among the peaks detected by said peak detection means andthat obtains an average delay differential among individual delayprofiles by averaging out a desired number of delay differentialsbetween the maximum peaks.
 13. An inter-branch delay differentialdetecting method in a radio receiving apparatus, wherein, a delayprofile is formed for each of individual branch received signalsreceived by a plurality of antennas, a peak is detected in each of theformed delay profile signals, and a maximum peak in each delay profilesignal is obtained from among the detected peaks, and an average delaydifferential between individual delay profiles is obtained by averagingout a desired number of delay differentials between the maximum peaks.14. The inter-branch delay differential detecting method in a radioreceiving apparatus according to claim 13, wherein, a delay profilesignal with a leading phase from among individual delay profiles isdelayed by an average delay differential among individual delayprofiles, and the phases of individual profile signals are adjusted thesame, and the delay profile signals of the same phase are combined. 15.The inter-branch delay differential detecting method in a radioreceiving apparatus according to claim 14, wherein, a peak phase isdetected from a combined delay profile signal obtained by combinationprocessing, and a timing obtained by shifting a peak phase by an averagedelay differential under a corresponding branch is set a decoding timingfor a branch received signal.
 16. The inter-branch delay differentialdetecting method in a radio receiving apparatus according to claim 13,wherein, a branch received signal with a leading phase from amongindividual branch received signals is delayed by an average delaydifferential among individual delay profiles, and the phases of theindividual branch received signals are adjusted the same.